The Neijiang was raised in Southwest China in the Sichuan Basin in China, where the climate is mild, agriculture is well developed, and the area is rich in feed supplies. Neijiang pigs are not as hardy as some other breeds, but are well-tailored to the environment they have developed in, thriving in the Sichuan Basin.

The pigs are comparatively large in size, with strong body constitution, and thick back fat. They are also hugely prolific; the young boar may mount the female at as early an age as 2 months, and mature spermatozoa are found in the epididymis at 71 to 78 days; gilts can be mated and become pregnant as early as 90 days after birth. The average litter size is 10.6, and there are 7 pairs of teats.